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 # Laser-interaction-in-fields-rate-equations-forces
- C++ code for laser interaction and forces
+
+Rate equations simulation of particles in fields
+
+All details are found in the USER GUIDE. Here is simply the most relevant part. Modifications (new versions) are in Modif_code.txt
+
+The program solves the rate equations to study laser excitation, forces (scattering + dipolar + magnetic + electric + coulombian
+interactions). 
+
+
+It has been developed under Code::Blocks and Windows. The inputs are 2 external files describing the levels (with information about their energy + linear or quadratic Stark, Zeeman effect) and the transitions lines (dipole transitions, photodetachement or photoionization cross sections).
+
+A file named Liste Param.h contains parameters to run the simulation such as:
+sample size, temperature, magnetic fields and for the laser beams (waist size and position, polarisation, power, linewidth, wavelength, ...). 
+
+A Kinetic Monte Carlo algorithm  evolves in motion (forces under extranal fields + optical dipole forces) and event (absorption or emission) 
+
+The output is writen in a file containing relevant information such as population in given levels and statistics about velocities (temperature), potential energy ... Output is also performed through 3D snapshots. 
+